Variability in Plasma Polymerization Processes - An International Round-Robin Study

This multi‐centre investigation explores the variability that results from using the power/flow rate ratio (W/F) to describe plasma treatment and plasma polymerization processes. Results from fourteen reactors of different design and spread across ten laboratories, showed that the chemistry of the treated and deposited polymer/plasma polymer films is highly variable between reactor systems, and that there was no clear pattern linking these variations to other properties of the reactor systems (e.g. pressure, volume, electrode configuration). Although W/FM provides a useful rule‐of‐thumb for process optimization within a single system, it does not provide sufficient information to enable the same plasma polymer to be produced on a different system. The variability of plasma treatments and processes in laboratory plasma systems is explored through a round‐robin study. Substantial differences are observed between reactor systems, both in the degree of plasma treatment, and the functional group retention and deposition rate of plasma polymerized acrylic acid. The results illustrate the importance of characterizing and understanding the effect of plasma properties directly.